The nervous system, in particular the brain, plays an essential role in a mammal's life. For example cognitive, emotional, social, sensory, motoric and regulatory functions are mainly determined by the brain. In the western society more and more diseases, disorders and problems with a proper functioning of the brain are becoming recognised. Young people increasingly experience damage to the brain, for example due to intoxications such as alcohol—or drug abuse, due to traumata such as traumatic brain injury (TBI), for example as a result of sport accidents, work accidents, car accidents and the like, or systematic malnourishment. Also during aging several deleterious changes occur in the nervous system and in particular in the brain. Malfunctioning of the brain is therefore especially a problem in the elderly and more in particular in the frail or malnourished elderly. In this group, several diseases and disorders which are associated with or find their cause in a badly functioning nervous system are therefore relatively frequently observed. Examples are several forms of dementia, such as vascular dementia, Alzheimer's disease, dementia with Lewy bodies; Huntington's disease, Parkinson's disease; mood disorders, such as the various forms of depression, but also other diseases or disorders like abnormal behaviour, for example during daily living, withdrawal from social events and indecisiveness.
Many lipid blends have been used in the manufacture of foods for improving brain function. For example WO 2006/118665 discloses a method of reducing protein aggregation in the brain of a mammal by increasing endogenous ketone levels. The latter can be achieved by administering medium chain fatty acids (MCT) and a low amount of digestible carbohydrates. WO 2007/001883 discloses the use of MCT and carnitine to improve mitochondrial function. U.S. Pat. No. 6,835,750 discloses the use of MCT in a dose of 0.5-10 g/kg body weight per day to treat Alzheimer's disease. However, it is generally known that administration of high doses of MCT may result in gastrointestinal discomfort. Furthermore, MCT administration results in a satiating effect which may decrease the amount that is consumed of subsequent meals. This is often undesirable in diseased persons or the elderly. Also the ketogenic character of MCT decreases with time, which would mandate the consumption of ever increasing amounts of MCT to obtain the same ketogenic effect. Further, MCT consumption may result in increased plasma levels of for example triglycerides, which is undesirable in persons who are at risk of developing cardiovascular or cerebrovascular disorders, such as the elderly and in obese persons. EP 1282365 discloses the use of a blend which comprises omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA's) and phospholipids in conjunction with specific B vitamins to treat vascular diseases and dementia. JP 10136937 discloses a total nutritional food comprising docosahexanoic acid, eicosapentaenoic acid and linoleic acid for activating the function of encephalic cells.
Lipid blends have also been proposed for the treatment of disorders, other than for the support of brain function. U.S. Pat. No. 5,886,037 discloses the use of a lipid blend which comprises 55-95 wt % MCT, 5-25 wt % ω-3 LCP and 0-3 wt % other fatty acids for treatment of dyslipidaemias. EP 1216041 discloses the use of a high amount (35-70 en %) of a lipid blend with 25-70 wt % MCT and ω-6/ω-3=2-7:1 in the manufacture of a food product for the treatment of sepsis or inflammatory shock. WO 2003/013276 discloses the use of 30-70 en % of a lipid blend which is rich in oleic acid (50-70 wt %) and specific amounts of ω-6 fatty acids and 1-10 wt % ω-3 fatty acids for increasing intramyocellular lipid levels in muscle cells, which is claimed to be beneficial for endurance athletes. On the other hand, also a blend with 40-65 wt % MCT and MUFA=0-30 wt % and 20-50 wt % LC saturated fatty acids is disclosed for decreasing the accumulation of intramyocellular lipids in an individual. EP 0175468 discloses the use of a mixture of docosahexanoic acid, eicosapentaenoic acid and gamma-linolenic acid (an ω-6 fatty acid) for the treatment of cancer.
Therefore there is a need for nutritional or pharmaceutical compositions which are suitable for enteral use by a patient in need of a support of brain function, which does not have the disadvantages of prior art compositions, which demonstrates a rapid effect, and which is convenient for use and palatable.
The inventors now have found that the use of a lipid fraction, in a specific formulation of the product and optionally in combination with a protein fraction, and/or other components provides these advantages over the prior art solutions for the support of brain function, in particular in the elderly.